Gabriele.vivinetto: Replacing page with 'Come scegliere il nome di un computer. E' un documento: [http://www.faqs.org/rfcs/rfc1178.html RFC1178 - Choosing a name for your computer] Spunti: *[http://it.wikipedia.org...'

2010-07-05T13:09:58Z

Replacing page with 'Come scegliere il nome di un computer. E' un documento: [http://www.faqs.org/rfcs/rfc1178.html RFC1178 - Choosing a name for your computer] Spunti: *[http://it.wikipedia.org...'

Show changes

Gabriele.vivinetto at 16:55, 4 June 2005

2005-06-04T16:55:17Z

New page

Come scegliere il nome di un computer.
E' un documento RFC http://www.faqs.org/rfcs/rfc1178.html

<pre>
Network Working Group D. Libes
Request for Comments: 1178 Integrated Systems Group/NIST
FYI: 5 August 1990

Choosing a Name for Your Computer

Status of this Memo

This FYI RFC is a republication of a Communications of the ACM
article on guidelines on what to do and what not to do when naming
your computer [1]. This memo provides information for the Internet
community. It does not specify any standard.

Distribution of this memo is unlimited.

Abstract

In order to easily distinguish between multiple computers, we give
them names. Experience has taught us that it is as easy to choose
bad names as it is to choose good ones. This essay presents
guidelines for deciding what makes a name good or bad.

Keywords: domain name system, naming conventions, computer
administration, computer network management

Introduction

As soon as you deal with more than one computer, you need to
distinguish between them. For example, to tell your system
administrator that your computer is busted, you might say, "Hey Ken.
Goon is down!"

Computers also have to be able to distinguish between themselves.
Thus, when sending mail to a colleague at another computer, you might
use the command "mail libes@goon".

In both cases, "goon" refers to a particular computer. How the name
is actually dereferenced by a human or computer need not concern us
here. This essay is only concerned with choosing a "good" name. (It
is assumed that the reader has a basic understanding of the domain
name system as described by [2].)

By picking a "good" name for your computer, you can avoid a number of
problems that people stumble over again and again.

Here are some guidelines on what NOT to do.

Don't overload other terms already in common use.

Using a word that has strong semantic implications in the
current context will cause confusion. This is especially true
in conversation where punctuation is not obvious and grammar is
often incorrect.

For example, a distributed database had been built on top of
several computers. Each one had a different name. One machine
was named "up", as it was the only one that accepted updates.
Conversations would sound like this: "Is up down?" and "Boot
the machine up." followed by "Which machine?"

While it didn't take long to catch on and get used to this
zaniness, it was annoying when occasionally your mind would
stumble, and you would have to stop and think about each word
in a sentence. It is as if, all of a sudden, English has
become a foreign language.

Don't choose a name after a project unique to that machine.

A manufacturing project had named a machine "shop" since it was
going to be used to control a number of machines on a shop
floor. A while later, a new machine was acquired to help with
some of the processing. Needless to say, it couldn't be called
"shop" as well. Indeed, both machines ended up performing more
specific tasks, allowing more precision in naming. A year
later, five new machines were installed and the original one
was moved to an unrelated project. It is simply impossible to
choose generic names that remain appropriate for very long.

Of course, they could have called the second one "shop2" and so
on. But then one is really only distinguishing machines by
their number. You might as well just call them "1", "2", and
"3". The only time this kind of naming scheme is appropriate
is when you have a lot of machines and there are no reasons for
any human to distinguish between them. For example, a master
computer might be controlling an array of one hundred
computers. In this case, it makes sense to refer to them with
the array indices.

While computers aren't quite analogous to people, their names
are. Nobody expects to learn much about a person by their
name. Just because a person is named "Don" doesn't mean he is
the ruler of the world (despite what the "Choosing a Name for
your Baby" books say). In reality, names are just arbitrary
tags. You cannot tell what a person does for a living, what
their hobbies are, and so on.

Don't use your own name.

Even if a computer is sitting on your desktop, it is a mistake
to name it after yourself. This is another case of
overloading, in which statements become ambiguous. Does "give
the disk drive to don" refer to a person or computer?

Even using your initials (or some other moniker) is
unsatisfactory. What happens if I get a different machine
after a year? Someone else gets stuck with "don" and I end up
living with "jim". The machines can be renamed, but that is
excess work and besides, a program that used a special
peripheral or database on "don" would start failing when it
wasn't found on the "new don".

It is especially tempting to name your first computer after
yourself, but think about it. Do you name any of your other
possessions after yourself? No. Your dog has its own name, as
do your children. If you are one of those who feel so inclined
to name your car and other objects, you certainly don't reuse
your own name. Otherwise you would have a great deal of
trouble distinguishing between them in speech.

For the same reason, it follows that naming your computer the
same thing as your car or another possession is a mistake.

Don't use long names.

This is hard to quantify, but experience has shown that names
longer than eight characters simply annoy people.

Most systems will allow prespecified abbreviations, but why not
choose a name that you don't have to abbreviate to begin with?
This removes any chance of confusion.

Avoid alternate spellings.

Once we called a machine "czek". In discussion, people
continually thought we were talking about a machine called
"check". Indeed, "czek" isn't even a word (although "Czech"
is).

Purposely incorrect (but cute) spellings also tend to annoy a
large subset of people. Also, people who have learned English
as a second language often question their own knowledge upon
seeing a word that they know but spelled differently. ("I
guess I've always been spelling "funxion" incorrectly. How
embarrassing!")

By now you may be saying to yourself, "This is all very
silly...people who have to know how to spell a name will learn
it and that's that." While it is true that some people will
learn the spelling, it will eventually cause problems
somewhere.

For example, one day a machine named "pythagoris" (sic) went
awry and began sending a tremendous number of messages to the
site administrator's computer. The administrator, who wasn't a
very good speller to begin with, had never seen this machine
before (someone else had set it up and named it), but he had to
deal with it since it was clogging up the network as well as
bogging down his own machine which was logging all the errors.
Needless to say, he had to look it up every time he needed to
spell "pythagoris". (He suspected there was an abbreviation,
but he would have had to log into yet another computer (the
local nameserver) to find out and the network was too jammed to
waste time doing that.)

Avoid domain names.

For technical reasons, domain names should be avoided. In
particular, name resolution of non-absolute hostnames is
problematic. Resolvers will check names against domains before
checking them against hostnames. But we have seen instances of
mailers that refuse to treat single token names as domains.
For example, assume that you mail to "libes@rutgers" from
yale.edu. Depending upon the implementation, the mail may go
to rutgers.edu or rutgers.yale.edu (assuming both exist).

Avoid domain-like names.

Domain names are either organizational (e.g., cia.gov) or
geographical (e.g., dallas.tx.us). Using anything like these
tends to imply some connection. For example, the name "tahiti"
sounds like it means you are located there. This is confusing
if it is really somewhere else (e.g., "tahiti.cia.gov is
located in Langley, Virginia? I thought it was the CIA's
Tahiti office!"). If it really is located there, the name
implies that it is the only computer there. If this isn't
wrong now, it inevitably will be.

There are some organizational and geographical names that work
fine. These are exactly the ones that do not function well as
domain names. For example, amorphous names such as rivers,
mythological places and other impossibilities are very
suitable. ("earth" is not yet a domain name.)

Don't use antagonistic or otherwise embarrassing names.

Words like "moron" or "twit" are good names if no one else is
going to see them. But if you ever give someone a demo on your
machine, you may find that they are distracted by seeing a
nasty word on your screen. (Maybe their spouse called them
that this morning.) Why bother taking the chance that they
will be turned off by something completely irrelevant to your
demo.

Don't use digits at the beginning of the name.

Many programs accept a numerical internet address as well as a
name. Unfortunately, some programs do not correctly
distinguish between the two and may be fooled, for example, by
a string beginning with a decimal digit.

Names consisting entirely of hexadecimal digits, such as
"beef", are also problematic, since they can be interpreted
entirely as hexadecimal numbers as well as alphabetic strings.

Don't use non-alphanumeric characters in a name.

Your own computer may handle punctuation or control characters
in a name, but most others do not. If you ever expect to
connect your computer to a heterogeneous network, you can count
on a variety of interpretations of non-alphanumeric characters
in names. Network conventions on this are surprisingly
nonstandard.

Don't expect case to be preserved.

Upper and lowercase characters look the same to a great deal of
internet software, often under the assumption that it is doing
you a favor. It may seem appropriate to capitalize a name the
same way you might do it in English, but convention dictates
that computer names appear all lowercase. (And it saves
holding down the shift key.)

Now that we've heard what not to do, here are some suggestions on
names that work well.

Use words/names that are rarely used.

While a word like "typical" or "up" (see above) isn't computer
jargon, it is just too likely to arise in discussion and throw
off one's concentration while determining the correct referent.
Instead, use words like "lurch" or "squire" which are unlikely

to cause any confusion.

You might feel it is safe to use the name "jose" just because
no one is named that in your group, but you will have a problem
if you should happen to hire Jose. A name like "sphinx" will
be less likely to conflict with new hires.

Use theme names.

Naming groups of machines in a common way is very popular, and
enhances communality while displaying depth of knowledge as
well as imagination. A simple example is to use colors, such
as "red" and "blue". Personality can be injected by choices
such as "aqua" and "crimson".

Certain sets are finite, such as the seven dwarfs. When you
order your first seven computers, keep in mind that you will
probably get more next year. Colors will never run out.

Some more suggestions are: mythical places (e.g., Midgard,
Styx, Paradise), mythical people (e.g., Procne, Tereus, Zeus),
killers (e.g., Cain, Burr, Boleyn), babies (e.g., colt, puppy,
tadpole, elver), collectives (e.g., passel, plague, bevy,
covey), elements (e.g., helium, argon, zinc), flowers (e.g.,
tulip, peony, lilac, arbutus). Get the idea?

Use real words.

Random strings are inappropriate for the same reason that they
are so useful for passwords. They are hard to remember. Use
real words.

Don't worry about reusing someone else's hostname.

Extremely well-known hostnames such as "sri-nic" and "uunet"
should be avoided since they are understood in conversation as
absolute addresses even without a domain. In all other cases,
the local domain is assumed to qualify single-part hostnames.
This is similar to the way phone numbers are qualified by an
area code when dialed from another area.

In other words, if you have choosen a reasonable name, you do
not have to worry that it has already been used in another
domain. The number of hosts in a bottom-level domain is small,
so it shouldn't be hard to pick a name unique only to that
domain.

There is always room for an exception.

I don't think any explanation is needed here. However, let me
add that if you later decide to change a name (to something
sensible like you should have chosen in the first place), you
are going to be amazed at the amount of pain awaiting you. No
matter how easy the manuals suggest it is to change a name, you
will find that lots of obscure software has rapidly accumulated
which refers to that computer using that now-ugly name. It all
has to be found and changed. People mailing to you from other
sites have to be told. And you will have to remember that
names on old backup media labels correspond to different names.

I could go on but it would be easier just to forget this
guideline exists.

Conclusion

Most people don't have the opportunity to name more than one or two
computers, while site administrators name large numbers of them. By
choosing a name wisely, both user and administrator will have an
easier time of remembering, discussing and typing the names of their
computers.

I have tried to formalize useful guidelines for naming computers,
along with plenty of examples to make my points obvious. Having been
both a user and site administrator, many of these anecdotes come from
real experiences which I have no desire to relive. Hopefully, you
will avoid all of the pitfalls I have discussed by choosing your
computer's name wisely.

Credits

Thanks to the following people for suggesting some of these
guidelines and participating in numerous discussions on computer
naming: Ed Barkmeyer, Peter Brown, Chuck Hedrick, Ken Manheimer, and
Scott Paisley.

This essay first appeared in the Communications of the ACM, November,
1989, along with a Gary Larson cartoon reprinted with permission of
United Press Syndicate. The text is not subject to copyright, since
it is work of the National Institute of Standards and Technology.
However, the author, CACM, and NIST request that this credit appear
with the article whenever it is reprinted.

References

[1] Libes, D., "Choosing a Name for Your Computer", Communications
of the ACM, Vol. 32, No. 11, Pg. 1289, November 1989.

[2] Mockapetris, P., "Domain Names - Concepts and Facilities",
RFC 1034, USC/Information Sciences Institute, November 1987.

Security Considerations

Security issues are not discussed in this memo.

Author's Address

Don Libes
Integrated Systems Group
National Institute of Standards and Technology
Gaithersburg, MD 20899

Phone: (301) 975-3535

EMail: libes@cme.nist.gov
</pre>

Come scegliere il nome di una macchina - Revision history

Gabriele.vivinetto: Replacing page with 'Come scegliere il nome di un computer. E' un documento: [http://www.faqs.org/rfcs/rfc1178.html RFC1178 - Choosing a name for your computer] Spunti: *[http://it.wikipedia.org...'

Gabriele.vivinetto at 16:55, 4 June 2005